Environmental Factors Affecting the Distribution of the Red- Legged Cormorant in Argentina: A Regional Scale Approach

Red-legged Cormorants (Phalacrocorax gaimardi) breed along a broad stretch of the Pacific coast and a section of the Argentinian coast on the Atlantic Ocean. To understand factors that might determine the breeding range along Argentina, physical and environmental characteristics of cliffed coastlines used by Red-legged Cormorants were compared with those not used. Red-legged Cormorant colonies were found in longer cliffed coastlines (mostly longer than 250 m) with shallow waters (median depth =12 m) and high sea productivity close to the coast (median chlorophyll a concentration = 4.4 mg/m3). Within the Red-legged Cormorants' breeding range the probability of occurrence of their colonies increased with the length of the cliffed coastline and decreased with the median sea depth around the colony. Mixed colonies were found in coastal areas with cliffs where the seawater close to shore was deeper (deeper than = 13 m). North of its distribution, sea productivity close to the coast was lower (median chlorophyll a concentration = 1.6 mg/m3) than within its distribution, and cliff faces were more exposed to the strong prevailing winds, which can blow eggs and chicks from their nests. South of its distribution, the climatic characteristics were more adverse to breeding success: higher precipitation, lower ambient temperature, and higher wind speed than within its distribution. At this scale of study (regional), new aspects of habitat structure of the Red-legged Cormorant, such as sea primary production, water depths and climatic features, were indentified. All these aspects could be affecting habitat selections by this species.Fil: Millones, Ana. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Frere, Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Magellanic penguin (Spheniscus magellanicus) embryos tolerate high temperature variations and low temperatures during incubation

Maintaining appropriate developmental temperatures during avian incubation is costly to the parents, so embryos may experience pronounced variations in temperature that can lead to embryo mortality and extended incubation periods, or that could affect the offspring phenotype in several bird species. The egg temperatures (N = 28 eggs) of free-living Magellanic Penguins (Spheniscus magellanicus) were recorded in a breeding colony in Puerto Deseado, Santa Cruz, Argentina. Three nests had atypical incubation patterns. Two nests experienced high temperature drops (average = 11.7 °C, minimum = 6.5°C, duration = 9 h) and another nest had a broad daily temperature range (max-min), i.e. 13.9 ±0.9 °C for the first egg and 14.1 ±0.8 °C for the second egg (range = 8-22°C during egg laying and 1837°C during advanced incubation). Thermal anomalies during incubation did not affect the embryonic viability, hatchling mass or fledging success. The survival of embryos despite these atypical incubation patterns may be an adaptive mechanism during the harsh weather conditions normally experienced by eggs throughout incubation.Fil: Barrionuevo, Melina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Frere, Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Wildlife Conservation Society; Estados Unido

The economic cost of seabird bycatch in Argentinean longline fisheries

Seabird mortality in longline fisheries is believed to be an important cause of the reductions in many seabird populations worldwide, and results in reduced fishing efficiency and economic losses for fishing companies. We estimated the economic cost of not using seabird bycatch deterrents in Argentinean longline fisheries, with the intention of encouraging adoption of mitigation measures in those fisheries. We conducted the study in the Argentine ling Genypterus blacodes and Patagonian toothfish Dissostichus eleginoides fisheries from 2001 to 2006 on three fishing vessels. Data on the incidence of seabird bycatch were collected by seabird observers specially trained in seabird identification and data on the catch rates of target species, cost of bait and fish were provided by the fishing company, supervised by Federal Inspectors from the Provincial Fisheries Agency. To estimate the bait loss, we set lines both with and without the use of deterrents (streamer lines, night setting and strategic discharge of offal) in both fisheries. Seabird bycatch varies temporally and geographically, so to estimate economic losses using deterrents in each fishery, we used different bycatch rates/1000 hooks registered for different periods and fishing areas. Bycatch rates in the absence of deterrents were two birds/1000 hooks and 1.53 birds/1000 hooks for the Patagonian toothfish and ling fisheries, respectively. These rates equate to the loss of more than 1.5 and 2 million dollars over a 10 year period for each fishery. When estimations are made with lower mortality rates, economic losses declined abruptly and were in the order of hundreds of dollars/fishing trip, for the same period of time. Results show that using deterrents, long term profits for the fishing company increase at a considerably high rate (the decrease in monetary loss is an order of magnitude), and the mortality of seabirds decreases by the same proportion (CPUE of seabirds decreases from tens of thousands to a few hundred). In these fisheries, the use of mitigation measures that reduce bait loss and seabird mortality represents a win-win situation with benefits to conservation and fishing companies.Fil: Gandini, Patricia Alejandra. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Frere, Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

Cormorants of the patagonian coast: population status, ecology and conservation

lo largo de la costa de Argentina nidifican cinco especies de cormoranes: el Cormorán Imperial (<i>Phalacrocorax atriceps</i>), el Cormorán Cuello Negro (<i>Phalacrocorax magellanicus</i>), el Cormorán Gris (<i>Phalacrocorax gaimardi</i>), el Biguá (<i>Phalacrocorax olivaceus</i>) y el Guanay (<i>Phalacrocorax bougainvillii</i>). En este trabajo se resume el estado del conocimiento actual, incluyendo información inédita, sobre los principales aspectos de la biología, la ecología, la abundancia y la distribución de las poblaciones de cormoranes en la costa argentina. Además, se presenta un análisis sobre los efectos y conflictos que las principales actividades humanas (transporte de petróleo, explotación guanera, turismo e interacciones con pesquerías) tienen sobre este grupo de aves marinas en la Patagonia argentina. Una serie de recomendaciones sobre estudios futuros para mejorar el manejo y la conservación de estas especies es presentada como conclusión del trabajo.Five species of cormorants breed along the Argentinean coast: Imperial Shag (<i>Phalacrocorax atriceps</i>), Rock Shag (<i>Phalacrocorax magellanicus</i>), Red-legged Shag (<i>Phalacrocorax gaimardi</i>), Neotropic Cormorant (<i>Phalacrocorax olivaceus</i>) and Guanay Shag (<i>Phalacrocorax bougainvillii</i>). This study presents the state of nowadays knowledge, including unpublished information, on different aspects of biology, ecology, abundance and distribution of cormorants’ populations in the Argentinean coast. It also presents an analysis of the effects and conflicts that the main human activities (oil transportation, guano explo.tation, tourism and interaction with fisheries) have on cormorants’ populations in the Argentinean Patagonia. Recommendations for future scientific studies to improve cormorant management and conservation are presented as the final conclusion of this study

New record of fleas (Hexapoda, Siphonaptera) parasitizing the Magellanic Penguin Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) in Argentina

Las pulgas del género Parapsyllus Enderlein, 1903 (Rhopalopsyllidae, Parapsyllinae) parasitan aves en forma exclusiva, en su mayoría marinas. Damos a conocer un nuevo registro de Parapsyllus longicornis (Enderlein, 1901) parasitando al Pingüino de Magallanes Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) en la Argentina. Este registro extiende el límite norte de distribución de esta pulga en el continente americano.Fleas from the genus Parapsyllus Enderlein, 1903 (Rhopalopsyllidae, Parapsyllinae) exclusively parasitize birds, mainly marine species. We present a new record of Parapsyllus longicornis (Enderlein, 1901) parasitizing the Magellanic Penguin Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) in Argentina. This new record extends the northern limit of distribution of this flea in the Americas.Fil: Lareschi, Marcela. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Estudios Parasitológicos y de Vectores. Universidad Nacional de La Plata. Facultad de Ciencias Naturales y Museo. Centro de Estudios Parasitológicos y de Vectores; ArgentinaFil: Procopio, Diego Esteban. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Frere, Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Morgenthaler, Annick. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Millones, Ana. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Barrionuevo, Melina. Universidad Nacional del Comahue; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

The diet of adult and chick rock shags (Phalacrocorax magellanicus) inferred from combined pellet and stable isotope analyses

The current information about the diet composition of the rock shag (Phalacrocorax magellanicus) in the SW Atlantic coast comes mainly from conventional pellet or stomach content analysis from a few locations situated in northern Patagonia (Chubut Province, Argentina). In this work, we studied the diet of breeding rock shags over several years at a colony from southern Patagonia (Ría Deseado, Santa Cruz Province, Argentina) using a combined technique of conventional diet assessment (pellet analysis) and stable isotope analysis of carbon and nitrogen. Our results confirm the importance of benthic prey and the low inter-annual variability in the diet of the rock shag. These results coincide with previous research in relation to the exploitation of slow moving, predictable, but low-energy density prey. The stable isotope mixing models, which was informed with prior data obtained from pellet analysis, allowed for the detection of subtle differences between the diet of adults and chicks, consisting in the incorporation of higher proportions of cephalopods, an energy-rich prey, in the diet of chicks. By comparing our results with the diet of the red-legged cormorant, which breeds in sympatry in the Ría Deseado Estuary and whose diet composition is strongly pelagic, we suspect a certain level of trophic resource partitioning between these rock shag and red-legged cormorant.Fil: Morgenthaler, Annick. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Millones, Ana. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Gandini, Patricia Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; ArgentinaFil: Frere, Esteban. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentin

Kelp gull ( <i>Larus dominicanus</i> ) as a carrier of pathogens in the patagonian coast

En este trabajo se estudió el transporte de enterobacterias por parte de la gaviota cocinera (<i>Larus dominicanus</i>), en un sector de la costa patagónica. A lo largo de un año (1995-96), un total de 100 individuos de distinto sexo y clase de edad, fueron capturados en el basural pesquero de Puerto Deseado. A cada uno de ellos se le realizó un hisopado cloacal y el sexo fue determinado por disección en el laboratorio. El análisis bacteriológico fue realizado por medio de pruebas bioquímicas convencionales, determinándose la presencia de al menos 10 especies de enterobacterias pertenecientes a los géneros: <i>Escherichia, Proteus, Citrobacter, Salmonella, Hafnia, Shigella, Enterobacter y Yersinia</i>. No se hallaron diferencias en las tasas de prevalencia entre sexos y clases de edades. La presencia de patógenos, para el hombre ó el ganado, en el tracto intestinal de las gaviotas a lo largo del año no mostró grandes diferencias, salvo para Proteus, que tuvo un pico de presencia durante la primavera y el verano y Citrobacter, durante la primavera. Salmonella typhimurium representa la entero bacteria encontrada de mayor riesgo para el hombre y el ganado y fue registrada durante gran parte del año. Aunque en el presente estudio no se investigan las tasas de infección bacteriana en humanos o ganado, la abundancia de gaviotas cocineras, sus hábitos alimenticios y la ubicación relativa de la ciudad (entre las colonias y el basural), convierten a estas aves en un probable candidato como vector de patógenos. Palabras Claves: Gaviotas, Larus dominicanus, enterobacterias, basurales, residuos, PatagoniaIn this paper we analyzed the carriage of pathogens by Kelp gulls (Larus dominicanus) in a portion of the Patagonian coast. During one year (1995-96), 100 individual s of different sex and age class were caught at fisheries tip of Puerto Deseado. Faecal samples were obtained from individual birds by cloacal swab and sex was determined at laboratory by dissection. We registered at least ten species of bacteria of eight genus (Escherichia, Proteus, Citrobacter, Salmonella, Hafnia, Shigella, Enterobacter and Yersinia), using standard biochemical technics. There were no differences in carriage rates between sexes and age classes. Camage rates were similar over almost all year, but Citrobacter was more abundant during Spring and Proteus during Spring and Summer. Salmonella typhimurium represents the more risky species for cattle and humans and it was found during most of the year. Despite this study was not focused to investigate the infection rates in humans or cattle, the abundance of kelp gulls, its pattems of feeding and movements, the relative location of the city (between fisheries tip and breeding areas), makes the species a very likely candidate for a pathogens vector

Incidental capture of seabirds in Argentinean side-haul trawlers

Between April 2008 and July 2015, we conducted a total of 18 trips on five different side-haul trawlers fishing within the Argentine Exclusive Economic Zone, monitoring 486 hauls. We observed 100% of the hauls and monitored trawl cables for 136.7 hours, about 5% of the trawl effort, to identify the levels of seabird bycatch from net entanglements and collisions with trawl cables. A total of 35 net entanglements of White-chinned Petrels Procellaria aequinoctialis, Great Shearwaters Ardenna gravis, Black-browed Albatrosses Thalassarche melanophris and Southern Royal Albatross Diomedea epomophora were recorded, all of which occurred during the autumn and winter. Additionally, 656 seabird collisions against trawl cables were recorded including 39 heavy, 96 medium and 521 light. Further, we recorded nine Black-browed Albatrosses and two Great Shearwaters potentially dead. Although in the study fishery the number of deaths in the trawl cables could surpass the number of birds incidentally killed in nets, the mortality rate caused by the latter type of interaction far exceeds those observed in nets from other trawl fisheries operating in the Patagonian Shelf. Fortunately, 26% of the seabirds entangled in the net were recovered and released alive, which indicates that awareness and training in safe bird handling and release may improve captured seabird survival rates. The main objectives of this work is to highlight a little-studied source of seabird mortality by entanglement, to generate discussion on potential technical mitigation measures for side-haul trawl fisheries, and to propose crew training in safe handling and release of seabirds as an immediate mitigation measure.Fil: Tamini, Leandro Luis. Albatross Task Force Argentina; ArgentinaFil: Chavez, Leandro Nahuel. Albatross Task Force Argentina; ArgentinaFil: Dellacasa, R. F.. Albatross Task Force Argentina; ArgentinaFil: Crawford, R.. Birdlife International; Reino Unido. Royal Society For The Protection Of Birds; Reino UnidoFil: Frere, Esteban. Birdlife International; Reino Unido. Universidad Nacional de la Patagonia Austral. Unidad Académica Caleta Olivia. Centro de Investigaciones Puerto Deseado; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentin

New record of fleas (Hexapoda, Siphonaptera) parasitizing the Magellanic Penguin Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) in Argentina

Las pulgas del género Parapsyllus Enderlein, 1903 (Rhopalopsyllidae, Parapsyllinae) parasitan aves en forma exclusiva, en su mayoría marinas. Damos a conocer un nuevo registro de Parapsyllus longicornis (Enderlein, 1901) parasitando al Pingüino de Magallanes Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) en la Argentina. Este registro extiende el límite norte de distribución de esta pulga en el continente americano.Fleas from the genus Parapsyllus Enderlein, 1903 (Rhopalopsyllidae, Parapsyllinae) exclusively parasitize birds, mainly marine species. We present a new record of Parapsyllus longicornis (Enderlein, 1901) parasitizing the Magellanic Penguin Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) in Argentina. This new record extends the northern limit of distribution of this flea in the Americas.Centro de Estudios Parasitológicos y de Vectore

New record of fleas (Hexapoda, Siphonaptera) parasitizing the Magellanic Penguin Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) in Argentina

Las pulgas del género Parapsyllus Enderlein, 1903 (Rhopalopsyllidae, Parapsyllinae) parasitan aves en forma exclusiva, en su mayoría marinas. Damos a conocer un nuevo registro de Parapsyllus longicornis (Enderlein, 1901) parasitando al Pingüino de Magallanes Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) en la Argentina. Este registro extiende el límite norte de distribución de esta pulga en el continente americano.Fleas from the genus Parapsyllus Enderlein, 1903 (Rhopalopsyllidae, Parapsyllinae) exclusively parasitize birds, mainly marine species. We present a new record of Parapsyllus longicornis (Enderlein, 1901) parasitizing the Magellanic Penguin Spheniscus magellanicus (Forster) (Aves, Sphenisciformes, Spheniscidae) in Argentina. This new record extends the northern limit of distribution of this flea in the Americas.Centro de Estudios Parasitológicos y de Vectore